official GDIY51PSU Help & Support Thread

[dmp]

I just ordered three transformers from Antek to power this psu, which is pretty affordable, $71 total
Two 25v, 5A rated, where the two secondaries will be connected one to the plus and one to the minus, for both +16/-16 and +24/-24
One 25v, 1A rated with the secondary connected in series for the 48v rail.
I tried this and got the correct output voltages.
Now, I am looking at the heat dissipation. Since for a linear regulator, Power dissipated = (Vin-Vout)*I, it seems that having a low input Voltage helps alot.
I couldn't find the min Vin for a given Vout (Vin-Vout = dropout voltage?) Does anyone know what this is for the LM350T?
Anyway, I think ordering 25v PTs for the power rails was not so bright. They also have lower: 15v,20v,22v - may be better.

 

[janczmok]

Just two easy questions:
(1) How much (in R) i have to put between the different rails and the LED's for each Power ?
(2) And how to wire the primary coil of the toroid ?

thanks for help. will post photos later.

 

[crisotop]

The series resistors for the leds are already on the psu board for each rail. Just put the two primaries in series for 230V mains voltage (combine two differently-colored wires and connect Phase + Neutral each to the remaining two wires).

hth, christoph

 

[zayance]

Ok here is my Swiss Cheese PSU finally finished  ;D, thanks to all the guys in the alliance for making this possible, really great!

 

[jsteiger]

That looks awesome zayance! Congrats on a beautiful build. I really like how the yellow LED's follow the curve of the 51x logo! Nice touch.

 

[[silent:arts]]

Ok here is my Swiss Cheese PSU finally finished

SWEET ;D ;D ;D
and with the alliance logo

any idea how much you paid for all the parts etc?

 

[geoff004]

That box looks great.
Can you tell me what the dimensions of it are?
Or what it is and where you got it?
thanks

 

[zayance]

any idea how much you paid for all the parts etc?

hmmm...., well in an approximative price, because the real PITA is always when you buy parts here and there, shipping adds etc.... BUT
All the box with shipping to France is 60 euros for modushop with aluminium panels
Engraving front and drilling back, 70 Euros, yes the logo is not cheap ;-), made by Franck btw  
Electronics, well i can't really tell, some from stock some ordered at Farnell and in a big order i made , so not cheap because of that, and i have spares now, you know most of the cost and if i had waited a little i would have bought them from Cemal now  :, but spare will always be used in the future so....
I went with Amphenol for connectors (i had in stock)
Heatsink for the regulators is about 12 euros, will not be as efficient as Cemal but i called it swiss Cheese, because i drilled holes on both side panels, and that was a lot of holes  , but will help heat dissipation.
Heatsinks for the rectifiers are home made, 2mm thick aluminium, drilles holes everywhere on it  ;D, painted in Black heat resistive paint, put that in the oven for fixing the paint, and ready to eat  , i sandwished the recifiers with two of them on each one, efficient, not efficient  ???, We will see, better than nothing anyway, thermal paste everywhere etc etc....

Screws and all are from stock, the mesh used to covers the top panel holes also, standoffs are from stock also
Patience and time from stock, coffee from stock   .

Anyway Thanks Volker for all this, can't wait to fill it up  ;D

PS: Add all the cabling, the drilled holes, tapping on some of them, etc..., well not cheap but looks nice and will i'm sure serve me for years  ;D

That box looks great.
Can you tell me what the dimensions of it are?
Or what it is and where you got it?
thanks

Thanks, Case is from Modushop (i just love them, will use them in most DIY i think), it's the Maggiorato but all black, you have to precise that on your order, because they have it but don't show it  , with top and bottom panels aluminium and not the ones they give stock, why aluminium, it's just for helping the overall heat dissipation, looks better also, but stock parts are great anyway, and they have heatsinks also in their website, just check the dimensions, or make sure it feets your needs, can email them.
Shipping from Modushop Italy to US could be expensive tough  
Anyway you'll have dimensions on their website.

Modushop case ref.1GX283
http://www.modushop.biz/ecommerce/cat037_l2.php?n=1

 

[sahib]

Good stuff. Great build. Congratulations.

I know I have not particularly been the fastest on completing the kit, but I thought I had to look into heatsink arrangement and do proper performance testing.

 

[zayance]

but I thought I had to look into heatsink arrangement and do proper performance testing.

Thanks to that Cemal, patience makes things better, and you know that 

 

[sahib]

This is our psu with example of internal wiring layout. However, the first two pictures belong to the prototype that I used for testing. I have replaced the heatsink with a cheaper alternative. It has the same surface area as the previous one (in fact slightly more) but I eliminated the T brackets. Also on the production ones I eliminated the ventilation holes for the transfromer as it does not heat-up enough to require them.

I used much larger silpad. Also the insulating washer is inserted through the back, which means the mounting screw is in contact with the regulator tab but insulated from the heatsink. This has got advantage. Not only it provides a tighter grip, but also eliminates the danger of regulator tab short circuiting to the heatsink/ground through a contact with the screw head.

The heatshrink is applied to the pins and they are carefully bent.

I soldered three way headers for convenient connection of the regulators. The wires are soldered onto the headers and heatshrink applied. Now you may immediately think why not use connectors. Possible, if you use high quality ones with the correct current rating. But my preference is to solder.

 

[Nobru]

Hi everybody;
Is there a connection to get the frame box for the moduls once they're build?
500 Format rock's!!

 

[jsteiger]

Hi everybody;
Is there a connection to get the frame box for the moduls once they're build?
500 Format rock's!!

Why yes of course. We are taking orders for them now. Full pricing and details can be found in the first post of this thread. http://www.groupdiy.com/index.php?topic=33849.0

 

[gemini86]

Quick question:

can one use a single 2x24v PT and supply both the +-24 and +-16 rails with one of each, letting the regulators bring the 24v down to 16 rather than having 4 separate rails?

I was just putting together an order on mouser and when adding the big rectifiers (627-D5SB80-7000), mouser notified me that people who bought this item, also bought: the rest of the 51xPSU parts list. That just made me chuckle... This 51x thing is really catching on.

 

[[silent:arts]]

can one use a single 2x24v PT and supply both the +-24 and +-16 rails with one of each, letting the regulators bring the 24v down to 16 rather than having 4 separate rails?

note: you really need separated windings for the positive and negative rails.
and bringing down 24V to 16V will be even more heat.
better idea would be one 2x24V and one 2x16V transformers.

 

[gemini86]

I was thinking to power +24/+16 with one and -24/-16 with the other, knowing that the increased dissipation would mean increased heat, but if I used a huge ass sink, can an lm317 do it? I'm not a man of money, so likely the rack would start off very slowly- I guess more like a lunch box. A couple 312s, Igor's new 1176, and possibly a simple one-bottle of my own doing, so the power doesn't have to be there in full force right off the bat. Once I get more spaces filled, I would surely upgrade the PSU.

Then again, I'm prone to shooting myself in the foot while trying to save a buck.

 

[dandeurloo]

I got my case and I have a few questions about the wiring.

1.  Does anyone have a good picture of how to wire up the Mains and the leads from the switch to the 240/120 switch on the back panel.

2. I could use a few pictures on or directions on how to wire up the LEDS and the fuse on the front panel.  I see where they go on the PSU board but in a few pictures it looks like they also split off to the 7 pin connector.  Are there any instruction I'm missing or am I one of the first to get the PSU case?

By the way, the case is amazing!  i think if I wasn't such a newbie this would be up and running already!

 

[sahib]

1. 120 /240V operation is as follows. Just ignore Mr Murphy's trick on me, the schematic says 220V.

As you can see from the image below the selector switch has two sets of contacts.

In 120V position two pairs are formed which parallels two 120V primaries.

In 240V operation the two on the left mate and the other two become idle. This connects two 120V primaries in series giving 240V operation. The colour code is important. Just stick to it.

Before you start to solder first check the contacts with your multimeter to establish their positions.

2. The wiring of the secondaries does not make much of a difference as the each rail of the power supply has its own bridge rectifier. However, it is a good practice to keep everything in the same phase. The way the wires leave the transformer is actually in order. I have connected as in below image.

3. You can power the LEDs as in the below picture. Apply ground to LEDs by using a black wire. Then power each LED by using a series resistor from its respective fuse immediately below.

4. In terms of 7 pin Neutrik the pin configurations are as follows;

1 = Chassis
2 = Gnd
3 = +16V
4 = -16V
5 = +48V
6 = +24V
7 = -24V

 

[Ptownkid]

Excellent info sir! Cheers

 

[Curran]

I have an Old School Audio 11 space 500 series rack and PSU. the PSU has two four pin XLR power hook ups. i am using one of them for the 500 rack and I would like to know how I can test the 2nd four pin XLR to figure out how to use it for one of the DIY51x racks. from what I can tell you guys are using a 7pin hook up for power, I am not gonna need the 24v power since I am really only using the rack for the classic api stuff from Jeff. any help or info will be awesome!!!